Human remains found beneath the Vatican have been identified as belonging to St Paul, Pope Benedict XVI said, apparently laying to rest the mystery of a tomb first discovered in the city in 2006.

Archaeologists found material and fragments of bone dating to the first or second century AD inside the tomb at the basilica of St Paul Outside the Walls in Rome.

Vatican experts claim the tomb's position, underneath the epigraph Paulo Apostolo Mart (Paul the Apostle and Martyr), at the base of the main altar is proof that it belongs to the apostle.

The pope said the tomb had not been opened but that a probe inserted through a small hole had revealed traces of purple linen decorated with gold sequins, blue material and red incense grains as well as the remains. "Small fragments of bone were carbon dated by experts who knew nothing about their provenance and results showed they were from someone who lived between the first and second century," he said.

"This seems to confirm the unanimous and uncontested tradition that these are the mortal remains of Paul the apostle," he said, adding that the discovery "fills our souls with great emotion".

The pope made the announcement from the basilica as he celebrated the end of the Pauline year, which has marked the 2,000th anniversary of the apostle's birth. It also comes a day after Vatican archaeologists uncovered what they believe to be the oldest icon of St Paul in a Rome catacomb, dating to the late fourth century.

St Paul was a Roman Jew who converted to Christianity after he saw a light on the road to Damascus. His letters in the New Testament are considered highly influential in Christian thinking.

Tradition holds that Paul was beheaded by the Emperor Nero around AD 62-65 and buried in a vineyard over which the Emperor Constantine built a basilica in 324. St Paul Outside the Walls is the second biggest church in Rome after St Peter's.